Shock-absorber.



LH. SAGER. SHOCK ABSORBBR.

APPLIOATION FILED MAY 3, 1910.

973,217. Patented ocn.18,191o.

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JAMES H. SAGER, OF ROCHESTER, NEW YORK.

SHOCK-ABSORBER.

Specication of Letters Patent.

Patented. @ctn i8, lg.

Application filed May 3, 1910. Serial No. 559,238.

fo all whom it may concern:

Be it known that JAMES H. SAGER, a citizen of the United States, andresident of Rochester, in the county of Monroe and State of New York,have invented certain new and useful Improvements in Shock-Absorbers, ofwhich the following is a specification.

This invention relates particularly to shock-absorbers for bicycles, andthe object of the invention is to produce a bicycleframe provided with ashock-absorbing device, this frame being of simple, compact andinexpensive construction.

Another object of the invention is to provide the frame with a novel andimproved pivotal connection between the rear fork and the crank-hanger,to permit the yielding movements of the rear fork necessary inconnection with the shock-absorber. To these ends the invention consistsin the novel construction hereinafter described, as it is defined in thesucceeding claims.

ln the drawings: Figure l is a side elevation of a portion of abicycle-frame in which the present invention is embodied, the upperportion of the frame being shown in'section to illustrate theconstruction of the shockabsorber, and the crank-hanger and associatedparts being shown in section on the line l-l in F ig. 3, looking fromleft to right in said ligure; Fig. Q is a vertical section, on anenlarged scale, on the line 2 2 in Fig. l, looking from righty to leftin said ligure; Fig. is a rear elevation of the crank-hanger andassociated parts; Fig. 4 is a section, on an enlarged scale, on the line4 4 in F ig. l, looking from right to left in said ligure and Fig. is aside elevation, showing in detail the connection between the rear staysand the slide.

The invention is illustrated as embodied in a bicycle-frame of the usualdiamondshape. The slide is in the form of a cylindrical member 5 whichis inclosed and guided within the horizontal upper frametube 6. The rearstays 7 of the frame are connected with the slide by means of a pin 8,which passes lvosely through the slide and through the upper ends of thestays and is provided at its ends with lock-nuts 9 by which the partsare adjusted closely but loosely together so as to permit relativepivotal movements of the slide and the stays. The pin 8 passes throughhorizontal slots 10 in the tube 6 to permit the slide to movelongitudinally in the tube, and washers 1l are interposed between thcstays and the slide to prevent contact between the stays and the tube 6.

The movements of the slide and the stays are controlled by a compressionspring l2 which is inclosed within the tube 6. The forward end of thespring rests against a plug 13 fixed in the tube, while the rear end ofthe spring engages the slide. In order to produce a slide of slightweight but with a long bearing surface, the slide is recessed in front,as shown in Fig. l, and a portion of the spring is received in therecess. To cushion rebounding movement of the slide a second spring leis placed behind the slide, in the tube 6, and the saddle-post l5 servesas an abutment for the rear end of this spring.

The rear stays 7 are pivoted at 8 to the rear ends of the rear fork 9 inthe usual manner, and the rear fork is also pivoted to the crank-hangerin a manner presently to be described. These pivotal connections,together with the movable slide, permit vertical yielding movements ofthe rear wheel when irregularities in the road surface are encountered,and in this respect the operation of the device is substantially similarto that of previous forms of cushion frames for bicycles. In the presentconstruction, however, the arrangement, of the slide and the rear staysprovides for a novel frictional action, while the employment of thehorizontal frame-tube to inclose the slide and the springs results in avery simple and compact construction. This construction is particularlyadapted for use in motorcycles, where it is desirable to make the frameas low as possible, since in the present construction theshock-absorbing elements are located entirely in front of the mast-tube16 of the frame.

The pivotal connection between the rear fork and the crank-hanger isillustrated particularly in Figs. 2 and 3. The side members of the rearfork are rigidly connected, at their forward ends, with a sleeve 17which contains the ball-bearings 1S upon which the crank-shaft 19 isjournaled. The sleeve 17 is journaled within the crankhanger 2O of theframe, this crank-hanger being of the usual cylindrical form and beingconnected in the usual manner with the mast-tube 16 and the forwardinclined tube 21 of the frame. To permit the intro duction of the sleeve17 in the crank-hanger the latter is slotted.y at the rear, from itsright-hand end, as shown in Fig. 3, so that the sleeve may be introducedthrough this end, the rear-fork members entering the slot as in Fig. 3.The slot is slightly enlarged above the positions normally occupied bythe rear-fork members, to provide for Vertical movements of the latterwhen the device is in operation. To retain the sleeve in thecrank-hanger and prevent end motion, the ends of the crank-hanger arethreaded to receive threaded cap-rings 22 which overhang the ends of thesleeve, as shown in Fig. 2.

To facilitate assembling the shock-absorber an opening 23 is provided inthe rear of the mast-tube 16, in line with the horizontal tube 6. Thesprings and the slide are introduced through the opening 23, the rearstays are then fastened to the slide by passing the pin S through theparts and Xing the nuts 9 in place, the sleeve 17 is then inserted, inthe manner above described, in the crankhanger, and the rear stays arefinally connected with the rear fork at the pivotal points 8.

I claim l. In a cushion-frame for bicycles, a pivotal connection betweenthe rear fork and the forward portion of the frame comprising, incombination with the crank-shaft, the crank-hanger and the rear fork, a.sleeve in which the crank-shaft is journaled, said sleeve beingjournaled in the crank-hanger and rigidly connectedy with the rearforli, and the crank-hanger being slotted at the rear to permit the rearfork and the sleeve to be inserted through the end of the crankhanger,and means for preventing endwise movement of the sleeve in thecrank-hanger.

2. In a cushion-frame for bicycles, the combination of an upper tube, amast-tube having a rearward opening in line with the upper tube, asaddle-post removably secured in the mast-tube, a slide in the uppertube, rear stays connected at their upper ends with the slide, a springin the upper tube for controlling forward movement of the slide, and asecond spring in the upper tube between the slide and the saddle-postfor controlling the rearward movement of the slide, the saddle-postserving normally as an abutment for the latter spring and beingremovable to permit the insertion of the spring and the slide throughsaid rearward opening of the mast tube.

JAMES H. SAGER.

Witnesses:

C. S. DAVIS, D. GURNEE.

